The Solar Impulse is a plane powered only by solar power. It does not require any fuel, only the sun shining on its 11,628 photovoltaic cells in order to fly. Powered by four 10HP engines, it can achieve speeds of up to 43 mph and is designed to fly for up to 36 hours without a break.

The plane has already completed flights from Switzerland to Spain and also to Morocco, but creator Bertrand Piccard is preparing to undertake a flight across America, which begins tomorrow with a number of technical flights to do some final checks. The actual 2013 Across America Mission will begin on May 1st.

The project is an impressive feat of engineering. The Solar Impulse has a wingspan of 63.4 meters, with power provided by 4 electric motors and lithium-ion batteries. Even so, it only weighs 1,600kg, but can fly with a maximum weight of 2,000kg. No help is necessary for it take off, it just needs a runway allowing it to achieve the required 22mph take-off speed.

During the Across America mission there’s 7 locations at which you may be able to see the Solar Impulse take off and land. The mission will start in San Francisco and then fly to Phoenix, Dallas, and then Atlanta or St. Louis, before continuing on to Washington D.C. and then finally landing in New York City. Dates will only be confirmed once the flight has begun and weather conditions assessed.

The current model of the Solar Impulse is named the HB-SIA. A second, larger version is named the HB-SIB and is in development. The aim is to fly that second craft around the globe in no more than 25 days in 2015. If successful, it will be an incredible achievement and hopefully has a positive impact on the design of future aircraft in terms of fuel conservation and taking advantage of green tech.